Figure 4.

Differential expansion of LCMV GP_66-77-specific CD4⁺Foxp3⁺ iTreg and CD4⁺Foxp3⁺ Treg in acute and chronic infection. (A) Frequency of LCMV GP_66-77-specific CD4⁺CD154⁺Foxp3⁺ iTreg in acute and chronic LCMV infection. Foxp3^GFP knock-in mice were infected with LCMV Armstrong (Arms) or clone 13 (Cl13) and the splenocytes from LCMV-infected Foxp3^GFP knock-in mice were prepared 8 and 35 days pi and used for 12 h-stimulation with LCMV GP_66-77 epitope peptide in the presence of PE-conjugated anti-CD154 antibody. The values in dot-plot denote the average of CD154⁺Foxp3^- Th, CD154^-Foxp3⁺ Treg, CD154⁺Foxp3⁺ iTreg cells gated on CD4⁺ T cells (B and C) The frequency and absolute number of LCMV GP_66-77-specific CD4⁺CD154⁺Foxp3⁺ iTreg and nonspecific CD4⁺Foxp3⁺ Treg cells. The splenocytes of infected Foxp3^GFP knock-in mice were prepared 8, 13 and 35 days pi, stimulated with LCMV GP_66-77 in the presence of the presence of PE-conjugated anti-CD154 antibody. The bars in graphs represent the average±SD of LCMV GP_66-77-specific CD4⁺CD154⁺Foxp3⁺ iTregs (B) and nonspecific CD4⁺Foxp3⁺ Treg (C) detected by intracellular CD154 staining in acute and chronic phase.